Reeling from what is potentially one of the most deadly auto-safety crises ever, Ford Motor Co.'s chief executive and Bridgestone/Firestone Inc. officials denied charges that they conspired to hide evidence of defective tires from Venezuelan authorities.

Meanwhile, U.S. safety regulators boosted to 88 the number of reported deaths that have been linked with accidents involving Firestone tires. The National Highway Traffic Safety Administration had previously been investigating reports of 62 deaths involving the tires. In...